One of the two reactors at Diablo Canyon nuclear power plant has been shut down for a refueling outage, PG&E announced Monday.
The reactor operated continuously for 525 days since its last refueling shutdown ended Nov. 13, 2010. No restart date was announced, but outages usually last about a month.
During an outage, workers replace about a third of the fuel in the reactor and perform thousands of maintenance tasks. About 1,000 additional temporary workers are brought in to do all the work.
Outages are also opportunities to replace or upgrade equipment. During this outage, a new digital process control system will be installed, replacing some analog equipment in the control room.
The new system will enhance operators ability to monitor the status of the plant and increase safety, said Tom Cuddy, a PG&E spokesman.
During the outage, the new equipment will be installed and tested, he said. In fact, the team will perform meticulous testing of more than 200 instrumentation loops.
Refueling shutdowns are normally scheduled for spring and fall when statewide demand for electricity is at its lowest. Diablo Canyon produces about 10 percent of the states power or enough for more than 3 million homes.